1. Field of the Invention
The present invention is generally related to a marine propulsion device and, more particularly, to a sterndrive unit that has an access opening which facilitates the disassembly and removal of a nut from the swivel shaft which connects a gimbal ring to a gimbal housing, or support structure.
2. Description of the Related Art
Those skilled in the art of marine propulsion devices and, more specifically, sterndrive units, are familiar with the structure of those devices and the manner in which a bell housing is supported by a gimbal ring and the gimbal ring is supported by a gimbal housing. In addition, those skilled in the art of marine propulsion devices are familiar with the manner in which a drive unit of a sterndrive system is pivotally supported for rotation about a steering axis and a tilt or trim axis.
U.S. Pat. No. 4,289,488, which issued to Weronke et al. on Sep. 15, 1981, discloses a sterndrive gimbal arrangement. It uses a gimbal ring to support the external propulsion unit. The gimbal ring is provided with an upper vertical square bore, a slot across the bore, and clamping bolts to provide full engagement with the square sides of a steering swivel shaft.
U.S. Pat. No. 4,565,532, which issued to Connor on Jan. 21, 1986, describes a sterndrive. A drive mechanism for a boat having the motor located inboard is disclosed. The mechanism includes a gear box located outboard of the transom with an input shaft extending toward the inboard motor and an outboard shaft extending aft toward a propeller shaft. A universal joint coupling is provided to drive the propeller shaft while a gimbal ring is employed to universally mount a propeller shaft housing such that the propeller may be used for steerage as well as forward thrust.
U.S. Pat. No. 4,645,464, which issued to Rawlings on Feb. 24, 1987, describes a steering and tilting means for a marine propulsion device. The device comprises a gimbal housing adapted to be fixedly mounted on a boat transom, a gimbal ring pivotally mounted on the gimbal housing for pivotal movement relative to the gimbal housing about a generally vertical axis, the gimbal ring including a lower end, and a support arm extending rearwardly from the lower end. A generally horizontal cross member extends across the lower end for preventing deflection of the support arm. A propulsion unit extends rearwardly of the gimbal ring and is pivotally connected to the gimbal ring for pivotal movement relative to the gimbal ring about a generally horizontal tilt axis.
U.S. Pat. No. 4,654,013, which issued to Bland et al. on Mar. 31, 1987, describes a steering means for a marine propulsion device. The device comprises a gimbal housing adapted to be fixedly attached to the rear of a boat transom, a gimbal ring, and a structure accessible from rearward of the boat transom for removably connecting the gimbal ring to the gimbal housing so as to provide for pivotal movement of the gimbal ring relative to the gimbal housing about a generally vertical steering axis.
U.S. Pat. No. 4,659,315, which issued to Bland et al. on Apr. 21, 1987, describes a hydraulic system for marine propulsion devices. The device comprises a gimbal housing adapted to be fixedly attached to the transom of a boat and including an end plate adapted to be generally aligned with the boat transom and having an opening, opposite sides, and a rear surface, the gimbal housing also including a first generally vertical side member extending rearwardly from one side of the end plate and a second generally vertical side member extending rearwardly from the other side of the end plate. A gimbal ring is pivotally connected to the gimbal housing for pivotal movement relative to the gimbal housing about a generally vertical steering axis.
U.S. Pat. No. 6,322,404, which issued to Magee et al. on Nov. 27, 2001, discloses a hall effect trim sensor system for a marine vessel. The sensor is mounted on a pivotal member of a marine propulsion system and a rotatable portion of the rotational position sensor is attached to a drive structure of the marine propulsion system. Relative movement between the pivotable member, such as a gimbal ring, and the drive structure, such as the outboard drive portion of the marine propulsion system, cause relative movement between the rotatable and stationary portions of the rotational position sensor. As a result, signals can be provided which are representative of the angular position between the drive structure and the pivotable member.
U.S. Pat. No. 6,371,820, which issued to Neisen et al. on Apr. 16, 2002, describes an integral piece gimbal ring and steering assembly for marine propulsion systems. The system has an integral piece gimbal ring and steering means. The system is made up of a gimbal housing affixed through the rear of a boat transom and a gimbal ring pivotally connected to the gimbal housing. The system is further made up of a steering assembly configured to provide pivotal movement of the gimbal ring relative to the gimbal housing about a steering axis. The gimbal ring and the steering assembly comprise an integral piece assembly.
U.S. Pat. No. 7,175,491, which issued to Davis et al. on Feb. 13, 2007, discloses an assembly system for a marine propulsion device. A marine propulsion system is configured to be assembled, as one unitary structure, into a marine vessel. A transom attachment member is provided and is attachable to both an engine and a drive unit to form a single marine propulsion system structure which can be lowered into an opening formed in a transom of a marine vessel.
The patents described above are hereby expressly incorporated by reference in the description of the present invention.
It would be significantly advantageous if a sterndrive device could be provided with an access opening to facilitate the disassembly of the gimbal ring from the gimbal housing while also providing support locations for the swivel shaft that are plural in number, spaced apart, and configured to support the shaft on two sides of a steering lever.